Abstract:
    Dark matter halos, as the basic unit for understanding the large-scale structure of the Universe, form hierarchically through merging. In this talk, I will discuss the evolution of important halo properties, such as concentration and anisotropy porperties, in the context of this hierarchical formation. We find that the internal properties of halos undergo significant, long-lasting, and universal changes during and after merger processes, which shape their present-day values. The merger-induced evolution can be physically explained by the dynamics of mergers, and multiple properties can be combined to inform the dynamical history of halos. I will also describe our work on the accretion and orbit of subhalos in galaxy clusters, and the anisotropic distribution of subhalos in host halos. Subhalos accrete onto clusters coherently, show different orbit modes correlated with their masses, and are preferentially distributed near the host major axis. These findings have implications for various subfields, such as gravitational lensing, the Local Group, and cosmology with galaxy clusters.